"They have to gain back the confidence of the retail investor in China as well as stabilize the market," Paul Pong, managing director at Pegasus Fund Managers, told CNBC. Until then, "there will continue to be a lot of Chinese companies coming to Hong Kong to list even though the market is not as good as before. But still, this is a very good place to do an IPO," Pong said.
Hong Kong's stock exchange is expecting to see the flows.
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"I think our IPO market for the second half will be quite strong," said Charles Li, the HKEx CEO, at a press conference. With the mainland IPO pipeline stopped up, "we will continue to see new flows coming in -- not only the ones that wanted to be here in the first place. We probably will be seeing more, other companies that are making a decision that are not able to alternatively access the domestic market may actually switch."
CRSC's offering is Hong Kong's fourth largest this year. In May, Huatai Securities, China's largest stock brokerage by trading volume, raised $4.5 billion, Legend Holdings, the parent company of computer maker Lenovo Group, raised around $2 billion in June and GF Securities raised around $3.6 billion in an April IPO.
—By CNBC.Com's Leslie Shaffer; Follow her on Twitter @LeslieShaffer1